Organic syntheses by means of noble metal compounds. XXXVI. Reactions of carbanions with cyclooctadienepalladium and platinum halide complexes and tetraphenylcyclobutadienepalladium chloride complex
Organic syntheses by means of noble metal compounds. XXXVI. Reactions of carbanions with cyclooctadienepalladium and platinum halide complexes and tetraphenylcyclobutadienepalladium chloride complex
A New Synthetic Route to Electrophilic Cyclopropane Derivatives from Olefins
作者:Nariyoshi Kawabata、Shinji Yano、Jiro Hashimoto、Jun-ichi Yoshida
DOI:10.1246/bcsj.54.2539
日期:1981.8
1-Bis(alkoxycarbonyl)-, 1-alkoxycarbonyl-1-cyano-, and 1,1-dicyanocyclopropane derivatives were obtained in 10–99% yields by the reaction of Br2C(COOR)2, Br2C(CN)(COOR), and KBr[Br2C(CN)2]4, respectively, with olefins and Cu2Br2 in dimethyl sulfoxide (DMSO).
Synthesis of gem-dialkoxycarbonylcyclopropane derivatives from olefins by the reaction with dibromomalonic esters and copper in dimethyl sulphoxide
作者:Nariyoshi Kawabata、Masami Tanimoto
DOI:10.1016/0040-4020(80)88047-1
日期:1980.1
A novel method for the synthesis of gem-dialkoxycarbonylcyclopropane derivatives is reported which involves the reaction of olefins with dibromomalonic esters and Cu in dimethyl sulphoxide. The reaction was applicable to a wide range of olefins and proceeded smoothly at moderate temperature to give the cyclopropane derivatives often in good yields. Cu was converted to Cu(II) bromide during the reaction
Preparation of diastereomerically pure 9-carboxybicyclo[6.1.0]nonane derivatives
作者:Eckehard Volker Dehmlow、Olaf Pl�ckebaum
DOI:10.1002/prac.19963380161
日期:——
Reactions of cyclooctene (1) with dibromocyanoacetic esters and copper(I) bromide give (8-10) : 1 mixtures of isomers (2, 3), not stereochemically pure compounds as reported by others. The stereochemistry is elucidated by independent synthesis of one diastereomer (3a). Carbenoid addition of alkoxycarbonylmethylene to 1 and 1,5-cyclooctadiene leads also to exo/endo adduct mixtures. Methods are developed to generate diastereomerically pure compounds (exo-7a, exo-8, endo-9, exo-10, endo-10) from these. Endo esters of this series undergo very facile base catalyzed epimerization.
KAWABATA NARIYOSHI; TANIMOTO MASAMI, TETRAHEDRON, 1980, 36, NO 24, 3517-3522